HOUSTON – They are the hidden side of the government's stepped-up efforts to track down and deport illegal immigrants: Toddlers stranded at day-care centers or handed over to ill-equipped relatives. Siblings suddenly left in charge of younger brothers and sisters.

Associated Press

Ondine Galvez-Smith, an immigration attorney from Catholic social services, talked to family members of the 361 workers picked up in a raid at a factory last week in New Bedford, Mass.

When illegal-immigrant parents are swept up in raids on homes and workplaces, the children sometimes are left behind – a complication that underscores the difficulty in enforcing immigration laws against people who have put down roots and begun raising families in the United States.

Three million American-born children have at least one parent who is an illegal immigrant; one in 10 American families has mixed immigration status, meaning at least one member is an immigrant here illegally, according to the Pew Center for Hispanic Research and the office of Rep. Jose Serrano, D-N.Y. Children born in the United States are automatically U.S. citizens and are not subject to deportation.

Last week in Massachusetts, most of the 361 workers picked up in a raid at a New Bedford leather-goods factory that made vests and backpacks for the U.S. military were women with children, setting off what Democratic Gov. Deval Patrick called a “humanitarian crisis.”

Community activists scrambled to locate the children, offer infant-care tips to fathers unfamiliar with warming formula and changing diapers, and gather donations of baby supplies. One baby who was being breast-fed had to be hospitalized for dehydration because her mother remained in detention, authorities said.

Child-care arrangements had to be made for at least 35 youngsters.

Officials of the U.S. Immigration and Customs Enforcement division released at least 60 of the workers who were sole caregivers to children, but more than 200 were sent to detention centers in Texas and New Mexico.

“What is going to happen to the children? These children are American-born,” said Helena Marques, executive director of the Immigrant Assistance Center in New Bedford. “There are hundreds of children out there without their moms, in tremendous need. These babies have become the victims of a problem that legislators can't seem to fix.”

One mother was located in Texas after her 7-year-old child called a state hotline set up to help reunite the families, authorities said. Patrick said the woman would be returned to Massachusetts.

Massachusetts sent 37 social workers to Texas on Saturday to interview some of the women under arrest. Massachusetts Health and Human Services Secretary JudyAnn Bigby said the parents must be interviewed to make sure their youngsters are staying with responsible adults.

Authorities said some of the women might be so afraid their youngsters will be taken away that they have refused to disclose they have children.

Immigration officials defended their handling of the raid, saying Immigration and Customs Enforcement made arrangements in advance with social service agencies to care for the children. Immigration spokesman Marc Raimondi said all immigrants arrested by the agency are interviewed to determine if they are the sole parent of their children. The agency then can grant humanitarian releases, as it did in 60 cases in Massachusetts.

“We can only base our response by what we are learning by (the state Department of Social Services),” Raimondi said. “What DSS has told us is they are not aware of any child who was left in an inappropriate or risky setting, nor have they had to put any child in foster care.”

As for the parents' ultimate fate, being a single parent or the family breadwinner offers no special protection against deportation, said another Immigration and Customs Enforcement spokesman, Mike Keegan.

“They made a decision to come into the country illegally,” Keegan said. “It's hard to believe that someone would not know of the consequences when they get caught.”

Rep. William Delahunt, D-Mass., said yesterday there would be a congressional investigation into the raid.

Under pressure to crack down on illegal immigrants, Immigration and Customs Enforcement has intensified enforcement activity around the country. The efforts have yielded results. Since last May, one particular crackdown, called Operation Return to Sender, has snared 13,000 people, while other federal initiatives have caught thousands of others. The raids have led to a growing outcry from immigrant advocates and activists who say thousands of families are being split apart.

After nearly 1,300 people were arrested in December in raids at Swift & Co. meatpacking plants in Texas, Colorado, Minnesota, Iowa, Nebraska and Utah, community activists reported hearing of scores of children left on their own. Swift donated $300,000 to United Way agencies to help the families affected by the raids.

In Houston, a newly formed coalition of community groups, churches and advocacy organizations is scrambling to help dozens of families struggling to stay afloat after a husband or wife was taken away. Residents of an apartment complex in Houston that has been raided several times have formed an emergency child-care network, which jumps in to care for children left alone by a deported parent.

“The Department of Homeland Security is just carrying out the law they have to carry out,” Urban Institute demographer Randolph Capps said. “Under the law, there is no legal basis for considering the rights of families. Congress may have to act for that to change.”

Serrano is sponsoring a bill now before the House Judiciary Committee that would give immigration judges more discretion in weighing the effect on families when deporting an illegal immigrant.

Any immigration legislation probably will have a tough time passing Congress in the current political climate, said Bob Stein, a political scientist at Rice University in Houston.

“Immigration reform seemed like something Democrats and Republicans could agree on, but partisan fighting and the presidential campaigns make it hard for any candidate to carry the battle,” Stein said.

Until 1996, immigration judges were allowed to consider family hardship when deciding whether to deport legal residents charged with certain crimes. That changed under a new immigration law.

“As a country, we should not put our youngest citizens at risk of hunger, homelessness and living without parents,” said Ali Noorani, executive director of the Massachusetts Immigrant and Refugee Advocacy Coalition. “Our immigration system has to be squared with values.”